The present invention relates to a retractable caster assembly which can be used to support a framework, such as as a pallet, on casters. Such an assembly is useful in providing a degree of mobility to loaded pallets which enable them to be shifted about in relatively small areas that would be inaccessible to a normal forklift truck.
It is well-known in the art to use pallets to transport or store materials. However, the maneuvering of pallets presents difficulties when inside of vehicles such as airplanes or trucks, which are either inaccessible to, or do not have a large area for normal forklift trucks. Thus, in positioning loaded pallets inside of vehicles, it has often been necessary to first place the loaded pallet into the vehicle by use of a forklift truck and then to separately attach small handtrucks or carriers to the pallet in order to raise the pallet and move it to the desired position within the vehicle. Such small trucks or carriers are cumbersome to carry about and take some time to affix to pallets.
One area of special interest is the loading of delicate scientific testing equipment onto airplanes. Due to the weight and nature of the equipment, it is necessary to use some type of device to transport and position the equipment inside of the airplane. At the same time, care must be taken to move the equipment with a minimum of disturbance into areas which are inaccessible in most aircraft to large forklift trucks. p In order to provide for the movement of such loads within aircraft, I have invented a retractable caster assembly and a pallet using such an assembly. The pallet may be moved by a forklift truck or by lowering the retractable caster assemblies, and thus lifting the pallet, so that the pallet can be maneuvered easily by a person on the extended casters of the assemblies. By making the caster assemblies in such a way that they are integral with the pallet, the nuisance of attaching separate pallet trucks or carriers, each of which must be affixed and adjusted separately to a pallet in order to support it and make it moveable, is eliminated. In addition, the invention offers a large mechanical advantage for raising a loaded pallet from a surface onto the casters of the assemblies. The mechanism for lowering and raising the casters also provides a hand support for use in maneuvering the pallet about.